Other Kinds of Manual Keys

The "Double Speed" Key - "Sideswiper"

 

Just when the first "sideswiper" came into existence does not seem to be known. It is based on the idea that sidewise hand movements should be easier and perhaps faster than up and down movements. According to records found and graciously supplied by Jerry L. Bartacheck, KD0CA, the J. H. Bunnell Co. patented their new "double-speed " key in 1888, and claimed that it was developed to overcome telegrapher's paralysis or "glass arm". Today this type of affliction is called "carpal tunnel syndrome". Those who used this new key did find its claims to be true - that sidewise movements are much more comfortable and natural, and that it did prevent or greatly reduce the risk of glass arm. This key for a time became popular and was often called a "sideswiper", and sometimes a "cootie key". However, Bunnell's key was rather expensive and easy to imitate.

 

To use it, the operator used his thumb and forefinger to move the paddle of the key lever alternately from one side to the other -- each direction closed the circuit, whether moved to the right or to the left. In this way he formed the successive dits and dahs for each character. For example, If the operator made the first element of a character to the left (L), whether it was a dit or a dah, its next element was made to the right (R), and so on, alternately so that his pattern of movement was L-R-L-R-L-R .. . . or R-L-R-L-R-L . . .

 

This back and forth motion often tends to lead to a sort of peculiar rhythm of its own, betraying the use of a "sideswiper".

 

A few operators, troubled with "glass arm" found relief simply by turning their straight key around 90 degrees so it could be used with a one-way sidewise motion. (This use is easy to do with a bug or keyer, which already uses sidewise motion.)

 

Commercially made double-speed keys were relatively cheap compared to the Vibroplex, and it was quite easy to make a good homemade one. No wonder that it became popular in wireless operations, especially among hams, for some years. (It does not seem to have been used much by landline telegraphers.) Perhaps its novelty was as much an attraction as its claim for higher speeds and lowered fatigue.

The double-speed key may have led later to the idea of the semi-automatic key, whose first good commercial version, the "Vibroplex" was introduced in 1904, and soon began to be widely used by commercial telegraphers.

 

Of passing interest in 1926 was a similarly connected key having two pushbuttons, like typewriter keys or pushbuttons, to be used with two fingers, called the "Cricket" by its manufacturer. The keys were to be used alternately to form the characters, as with the "sideswiper". It never became popular.

 

The "BUG"
Historically the Martin semiautomatic key, introduced in 1906 as the "Auto" and later as the "Vibroplex" - commonly called a "bug" - is listed here second because of its greater mechanical complexity and difference in use. The patented Vibroplex, by making dots automatically (by the sidewise vibration of its elastically mounted arm), relieved much of the operator's effort (although he still had to form the dashes manually), and increased his speed potential, while reducing the risk of "glass arm" (by sidewise movement and division of labor between thumb and fingers).

 

In its various models it became very popular and has been widely used up to the present time. There have been many imitations, a few of which also produced automatic dashes. Normal (right-handed) models formed the dits automatically with a right-wise movement of the thumb and the dahs manually with a left-wise motion by one or two fingers against a paddle assembly. A few designs produced by a few manufacturers provided automatic dahs with by a second vibrating arm.

 

On the Australian landlines bug-keys were known as "jiggers". Those issued by the Sydney GPO Telegraph Office in 1946 had 3 knobs, two of them controlled separate swinging arms, one for automatically forming dits and one for automatic dahs and the third for manually controlled dahs. The knobs could be positioned at either end of the base-plate for easy use by right or left handed people. I have no information as to how these were used.

 

Using A Bug
A "bug" should not slip on the table, and its paddles should be about 2-1/2 inches above the tabletop. Most teachers recommend a light touch, pivoting the hand on the knuckle of little finger and using as combination of finger action and rolling wrist-motion. (Long-time speed champion Ted McElroy, however, said the wrist and elbow should be off the table, and a full, free swing of the arm used.) We may suspect several different styles are equally satisfactory. (It has been suggested that by holding a pencil in the same hand while sending will help one learn to relax.)

 

Bug sending should duplicate good hand-key sending. Handle it easily. Do not grip its paddles, but only allow the fingers or thumb to touch the side you are pressing on -- not touching the other side. When a bug is used for radio work there is a tendency to make the dits relatively too light. As compared to telegraph landline sending, radio requires a heavier style to put the signal through static and interference, and a heavier key will help do this. So be sure to set heavy enough dits that they are not likely to be swallowed up by moderate static or interference.

 

Setting the Adjustments of a Bug
Like all keys, bug adjustments are a highly personal matter, varying from one operator to another. They are also sensitive to the range of speed. For example, a bug set for 35 wpm operation will do poorly at 18, and vice-versa. -- Remember the rule: NEVER readjust another operator's bug!

 

Hugh S. Pettis, K3EC, recommends the following as optimum bug settings:

 

· It is to be understood that operator's personal comfort and ease of operation govern the details of setting the adjustments.

· First, set the adjustments for paddle displacement so that it moves a comfortable and equal amount for dits and dahs.

· Set the spring tensions for comfort of paddle operation.

· Set the movable weight on vibrating arm for the speed desired.

· Dit weighting is determined by the distance of the stationary dit post from the contact on the vibrating arm.

 

He cites a common technique for setting correct dit duration (a dit equals unit space) is to clip an ohmmeter across the bug terminals. First, set it for full scale while holding the paddle against the dah contact. Then adjust the stationary dit post contact until it gives a mid-scale reading for a series of dits, and finally settles on a full scale reading - a closed circuit. His personal preference is for the dits to taper off to a closed circuit after about ten dits. More dits will give a lighter weighting, and if the series leaves the circuit open, it is too light. Fewer dits will produce a heavier weighting, and if it is fewer than eight, the nominal (8 dit) error signal cannot be made.

 

Robert R. Hall W9CRO recommends: (Some adjustments are interactive.)

 

· Adjust top and bottom pivot bearings so contacts are all on same level, just tight enough so that side play is barely perceptible.

· Set the armature (the movable part controlled by the key tabs) stops:--

· Adjust the dah stop screw so the armature just touches the damper when held against this stop. (Damper contact should not be more than just enough to stop the swing.)

· Adjust the dit stop screws so that end of the armature will oscillate when it is moved against this stop with a brisk paddle movement of about 1/8 inch.

· The tension of the armature return spring should not be heavy, but just enough to return the armature to the right hand stop screw without any bounce, and without any tendency to bounce off the damper.

· Set the "dit" action very carefully:

· Set armature weight(s) about 3/4 of the way to the slowest speed. Then,

· Push the armature paddle to the dit position and hold it there until motion stops, and continue holding it there while adjusting the contact screw so that it just makes firm contact (but not so light that it arcs or misses). Some previous adjustments may need correction now.

· Set the dah action:

· Set the contact adjusting screw (which is also the stop) so the paddle moves about 1/8 inch.

· Its spring should be set to give about the same paddle pressure as for dits.

Sending With A Bug
Key smoothly and easily with a minimum of effort. Let the bug do the work - you just control it, with the arm resting on the table, touching the paddles loosely (lightly) between thumb and forefinger. Control it without much motion of the hand or fingers. A slight twist or roll of the wrist will change from the dit to the dah side. Relax and enjoy it. Don't bat out the dits and dahs out with thumb and forefinger so widely separated and so hard that it tends to push bug around.

 

There is a marked tendency among some bug users to set the dits too fast relative to the hand- formed dahs and spaces. Hand-formed spaces tend to become too long in proportion. The result is often a choppy sounding code or to signals which are certainly readable, but tiring to listen to and read. Katashi Nose KH6IJ points out that "at high speed one cannot put much force on the paddles." He also said that "If you move your whole arm, the law of inertia prevents you from attaining high speeds."

 

Keyers
Keyers are electronic devices controlled by paddles similar to those on a "bug" for automatically making dits and dahs, and often incorporate other useful operating features, including buffers and memories. Many include "iambic" type of operation by a "squeezing" motion, which provides for alternate dits and dahs, which further automates sending and in this way reduces total effort. An iambic keyer will always produce perfect characters, even though they may not be used in our code.

 

Katashi Nose here says, "If you have already mastered a bug, it will take about three weeks to convert to electronic-key sending. Once you are converted, you are hooked because now your bug fist is ruined [ed. for most people]; an entirely different technique is required." If your keyer has "forced character spacing" (FCS), use it! This may take several weeks practice, but your sending will be real armchair copy. It is worth the effort.

 

Keyboards
Finally, the keyboard (including the use of electronic computers with programs for using their keyboards) automatically makes all characters from a typewriter type of keyboard. Both keyers and keyboards often include teaching programs for learning the code and/or improving code abilities, as well as having memories for various purposes. This is about the ultimate in code production. (Machine sent CW is considered almost a "must" for good copy when signals are very faint, including QRP-- and for very high speed work (hand sending just won't hack that.)

 

Keyboards also have much to offer the beginner in learning the code initially and for improving one's skills. What may be possible hand-key speeds?

 

Psychological testing shows the average rates at which people can tap a fingers: -
On the High side: 9.7 per second, or 576/minute, (300 in 31 sec)
Average: 8.6 per second, or 516/min. (300 in 35 sec.)
On the Low side: 6.7 per second, or 402/min. (300 in 45 sec.)

 

If we assume that a dit is one "tap" and a dah is equal to two "taps" (two nerve pulses: one down and one up), then we may say:

 

Taps	Letters	Group Frequency	Taps x Frequency
1	E	0.130	0.130
2	T I	0.166	0.332
3	A N S	0.214	0.642
4	D H M R U	0.192	0.768
5	B F G K L V W	0.124	0.620
6	C O P X Z	0.139	0.834
7	J Q Y	0.024	0.168
Average per letter		1.000	3.494

Average for five-letter word = 17.47 taps.

 

At this rate, assuming the above rates can be maintained for periods of time needed to send messages, news, etc., the slowest keying rate would be 23 wpm, the average 30 and the highest 33 wpm.

 

An Interesting Bug
The Sydney Australia GPO Telegraph Office in 1946 produced a bug that had two separate swinging arms for dots and dashes. There were 3 knobs: one for dits, one for automatic dahs and one for manually controlled dashes. The knobs could be positioned at either end of the base-plate for easy use by right or left handed people.

Chapter 11

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